Extole, a startup offering tools for brands to manage their "social advocacy" programs, has raised $7.5 million in new funding. The round is a follow-on to the $10 million Series C that Extole raised about a year ago, and it comes from existing investors, including Shasta Ventures, Norwest Venture Partners, Redpoint Ventures, and Trident Capital. The company has now raised a total of $29.9 million.